Personal audio devices, such as mobile/cellular telephones, cordless telephones, and other consumer audio devices, such as mp3 players, are in widespread use. Performance of such devices with respect to intelligibility can be improved by providing noise canceling using a microphone to measure ambient acoustic events and then using signal processing to insert an anti-noise signal into the output of the device to cancel the ambient acoustic events. Because the acoustic environment around personal audio devices such as wireless telephones can change dramatically, depending on the sources of noise that are present and the position of the device itself, it is desirable to adapt the noise canceling to take into account such environmental changes.
Some personal audio devices also include equalizers. Equalizers typically attempt to apply to a source audio signal an inverse of a response of the electro-acoustic path of the source audio signal through the transducer, in order to reduce the effects of the electro-acoustic path. In most traditional approaches, equalization is performed with a static equalizer. However, an adaptive equalizer may provide better output sound quality than a static equalizer, and thus, may be desirable in many applications.